Scalable conformal electronics based on roll-to-roll exfoliated van der Waals semiconductors
Integrating electronic devices onto surfaces with complex topography such as skin, textiles, and biological tissues requires fabrication strategies that combine mechanical conformability with high electronic performance and scalable manufacturing. While two-dimensional (2D) semiconductors are promising materials for such applications, their integration into conformal electronic systems remains challenging because scalable liquid-phase processing typically yields films with limited electronic performance, whereas high-quality CVD materials require complex synthesis and transfer processes. Here we establish a scalable route toward conformal electronics based on semiconducting van der Waals materials by combining high-throughput roll-to-roll mechanical exfoliation with commercially available temporary tattoo and waterslide decal transfer substrates. This approach enables the fabrication of ultrathin MoS2-based electronic devices that can be transferred onto rough and curved surfaces such as skin, synthetic leather, and plant leaves. The resulting devices operate reliably after transfer and exhibit strong electronic and optoelectronic performance, including photodetectors with responsivities up to approximately 3.5 A W$^{-1}$, thermistors with temperature coefficients of resistance from -2 to -3.5% per degree Celsius, and ionic-gel-gated field-effect transistors with mobilities reaching approximately 18 cm$^2$ V$^{-1}$ s$^{-1}$.